Retrievable subsurface safety valve

ABSTRACT

A multi functional assembly adaptable within a tubing string conduit to serve as a safety valve against the possibility of a blow out. Both surface and subsurface controllable, it offers both a partially retrievable or totally retrievable system that allows unbiased and unlimited work over and wire line access to an entire tubing string and can provide safety for down hole well work. The preferred invention comprises a housing mandrel system including closure elements reciprocally mounted vertically within the safety valve conduit that when unengaged provides unrestricted flow and when engaged provides restriction amounting from limited flow to complete closure of a tubing string. The invention provides operational options to function hydraulically and mechanically while having the additional capability of being remotely controlled automatically, electronically, and manually. The hydraulic and mechanical activation systems of the safety valve can be set to operate individually, simultaneously and selectively within the housing mandrel conduit.

TECHNICAL FIELD OF INVENTION

This invention is related generally to safety valves, in particular to asubsurface safety valve which includes a plurality of blocking means andbypass tubes for controlling flow through tubing string.

BACKGROUND OF INVENTION

It is alarming that there is an ever growing number of wells that use nosafety system whatsoever down hole. Regulatory and environmentalagencies are now calling for wells to be equipped with down hole safetyvalves prior to completion. There are a great number of producing wellsthat operate with a high pressure within the tubing string. Most all ofthese use some sort of safety equipment with the large majority beingabove surface safety systems commonly referred to as “blow outpreventers”. While most of these units are very well built and havefairly good holding power, they still cannot offer the crucial stabilitythat the earth provides below the surface. Furthermore, many of the morepopular systems in use today are actually utilizing technology that hasbeen in use for decades that has seen little to no effective improvementover the years.

System failures and damage to surface equipment in wells and pipelinescan result in the uncontrolled release of reservoir and productionfluids and hydrocarbons. These failures, often caused by the failure offaulty and unreliable safety equipment, can be the cause of all kinds ofdisastrous effects. Once released, foreign elements within theproduction flow can cause a large number of harmful effects such asdeaths and injuries to humans and wildlife, destruction of naturalenvironment, and financial loss. There are several different causes ofthis type of failure. First, production wells and pipeline systemsoperate with pressure within their tubing strings. Failure can occurwhen this pressure becomes too great. Second, flow itself can wear downand damage various components within the tubing string, especially whenthe flow contains abrasives such as sand and other harmful matter oftenfound to exist within the tubing string. These damaged components makewells and pipelines more susceptible to failure. For these reasons, newspecialized safety equipment that can effectively restrict theproduction flow should be used to control the flow of wells andpipelines in order to effectively address and prevent these occurrencesfrom happening.

Safety equipment can be positioned above or below the surface. Surfaceunits, while maintaining control of various minor fluctuations or spikescommonly occurring in production flow, may not provide the necessarylevel of protection needed in the event of a high pressure surface leveldisaster or failure. For this reason, subsurface safety equipment,widely referred to as down hole safety valves, act as a failsafe and areused to close or “shut in” producing wells in the event of such anemergency.

There are basically two types of conventional subsurface safety valves:surface controlled and subsurface controlled. As the name suggests,surface controlled safety valves are controlled from the surface,generally with an electronically operated control panel. This equipmentis usually either tubing retrievable requiring a work over or wire lineretrievable which may be run on a slick line or a wire line. In thesesurface controlled safety valves, an external control device is used toconnect the safety valve to the surface control system. The majorproblem with surface controlled safety valves is that they require inputfrom a source that is physically distant from the safety valve. Thisadded complexity increases (1) the cost of the valve, (2) the cost tooperate the valve, (3) the cost to operate the production well orpipeline, and more importantly (4) the likelihood of the valve'sfailure. Most subsurface controlled safety valves usually employ eitherflow or pressure sensitive devices to close the valve and most alwaysemploy complex mechanical systems. Typically, both of these type safetyvalves are adjoined to the tubing string so that the entire productionflow is directed through them. These units can be damaged by theirexposure to the flow elements within the tubing string, such as sand,paraffin, or other harmful matter within the tubing string. Over timethe constant exposure to these abrasive elements contained within theproduction flow eventually wears down virtually all of the exposedmoving parts of these valves resulting in the subsequent failure of thewell or pipeline. This is especially true of the ball and flappervalves. Similarly, bellows pressure sensitive devices are alsounreliable because they are susceptible to damage sustained duringextreme pressure differentials. Aside from damage such as warping, fluidleakage, paraffin build up, and the like, their slow, low forcemovements can cause their closing valves to seat improperly.Additionally, conventional safety valves unduly restrict normal conduitflow and block access to the well bore. If flowing conditions sustain aconsiderable change, which is a likely event over the lifetime of awell, the preset pressure settings in these safety valves may also needto be changed. Along with any other servicing, removal, or repairsinvolving the safety valve, this may require a work over.

It is an object of this invention to provide a retrievable safety valvethat can selectively restrict the flow of a well from a minute flow to acomplete halt of flow.

It is an object of this invention to provide a subsurface safety valvethat can be preset to automatically activate at a specific flow orpressure rate.

It is an object of this invention to provide a safety valve that canrestrict flow in a horizontal pipeline.

It is an object of this invention to provide a safety valve that can beactivated by hydraulic means.

It is an object of this invention to provide a safety valve that can beactivated by mechanical means.

It is an object of this invention to provide a safety valve that can beactivated electronically from a remote location.

It is an object of this invention to provide a safety valve that can beactivated manually from a remote location.

It is an object of this invention to provide a safety valve that afteractivation can be reset without having to pull the safety valve from thewell.

It is an object of this invention to provide a safety valve that iscapable of having the blocking means retrieved from the well orrepositioned in the well without the expense of a work over job.

It is an object of this invention to provide means of providing safetyduring wireline jobs.

It is an object of this invention to provide a means to help plug anon-producing well.

PRIOR ART SEARCH RESULTS October, 2010 By a Professional Patent SearchAgent at the USPTO, Alexandria, Va.

Numerous US patents of above and below ground safety devices werereviewed that were in the same field as this invention. The fieldssearched were as follows: 165/55. 250.08, 319-321, 338, 339. 341, 344,345. 373, 377, 378, 379, 380, 381. Primary examiner Dang, in class 166was consulted on this search.

The results found the following patents to be relevant, however, noneexactly as disclosed.

1. 4860826—Apparatus for sealing a tubing string in a high pressure wellbore—This device is an above ground storm choke that uses a tubingpiston closure device that is actuated by a pressure sensing device.

2. 4307783—C. P. Lanmon—Method and apparatus for conducting wirelineoperations during blow out conditions in oil and gas wells This is anabove ground system that is designed to protect wire line jobs fromsudden blow outs during the down hole work.

3. 4202368—Neil H. Akkerman—Safety valve or blow out preventer for usein a fluid transmission conduit—An above ground storm choke that uses apiston to block a preset limit of flow.

4. 3695349 Fernando Murman—Well blow out preventer control pressuremodulator Above ground bop

5. 3561723 Edward Cugini—Stripping and blow out preventer device Arotary bop

6. 2233077 C. P. Gillespie—Well Controlling apparatus Above groundsystem

7. 5875841 Andrew Wright—Oil well blow out preventer—above ground bopdevice

8. 5988274 Kelly Funk—Method of and apparatus for inserting pipes intowells has a piston like center piece with centrally placed closureplates that come together and meet to close off pipe.

9. 6913084 Anthony Boyd—Method and apparatus for controlling wellpressure while undergoing subsurface wire line operations Very complexdown hole system with surface control box.

10. 6938696 L. Murray back—pressure adapter pin and method of use Aboveground bop.

DISCUSSION OF PRIOR ART

While the average cost of installing a safety valve is relatively low,the expense incurred when they need repair or servicing can be highespecially in the cost of lost time and production. Most of thesedevices are placed within a tubing string typically allow for only asmall flow passage which significantly restricts the normal conduitflow. This also is very costly. Often, access to the well bore isprohibited without removal of the safety valve and the connecting tubingstring. Additionally, many of these valves must be replaced after a veryshort time due to the tremendous wear caused by the abrasive materialspassing through the small valve openings. Many of the conventionalsafety valves are designed to have continuous flow passage through theexposed working parts resulting in an increased amount of weareventually causing a breakdown of the system. Even though proponents ofthe conventional devices in use today claim a high degree ofreliability, they can, nonetheless, be damaged by their exposure to theflow elements within the tubing. As stated above, while most of the artthat is being used now has been known for decades, the subsequentimprovements still have the serious drawbacks. The principal one beingthat of forcing the upward production to go through a virtual labyrinthof flow restricting and easily damaged components instead of simplyallowing it to go around the blocking means. Not only do theysignificantly restrict flow, but if flowing conditions sustain aconsiderable change, which is likely to occur during the lifetime of awell, the preset pressure settings are likewise subject to change. Thesechanges can go unnoticed for years causing not only lost production, butalso elevating the risk of blowouts and other well damage. When theseproblems are made know, it may be necessary to remove the equipment fromthe well either to replace them or readjust the shut down settings.Whatever the reason, repairing or resetting these tools will involve aworkover. This along with the lost production and the equipment costs isterribly expensive.

In addition to the drawbacks of the equipment described above, othercostly problems involving some of the components of these safety valvesare as follows:

The use of bellows pressure sensitive devices is unreliable due to thedamage sustained during extreme pressure differentials. Aside from thedamage due to warping, fluid leakage, and paraffin buildup, their slow,low force movements can cause their closing means to seat improperly.

The main problem with the ball and flapper valves is their constantexposure to the well elements. Corrosion and damaging elements such assand, paraffin, and the like can damage the working mechanisms of thesedevices causing them to fail.

Most of the above and below ground safety devices have many workingparts that are constantly exposed to the elements within the well.Indeed, for these devices to work properly, all of their parts mustfunction properly. If not, then the entire system is subject to failure.Nearly all of these type down hole safety valves in use today cannot bereset down hole if they malfunction or shut off a well. Because of this,that equipment must be removed from the hole to either be replaced orreset. This requires an expensive work over job.

Blowout occurrences during wire line work are rare, but with existingdown hole safety equipment the threat remains.

SUMMARY OF THE INVENTION

In accordance with the invention, the problems of safety, restrictedflow, obstructed access to the well bore, unnecessary operation costs,complex mechanical systems, and necessity of work over jobs are solvedwith a down hole flow limiting valve with retrievable blocking elementsthat are not subject to the harmful elements contained of the upwardproduction flow. While this invention provides a new and reliable meansfor emergency blockage of a down hole tubing string, it also providesmeans for selectively regulating (choking) the upward flow from aminimal flow restriction to complete blockage. It also provides meansfor automatically resetting the safety valve without the need for theexpensive procedure of pulling the tubing string and it provides failsafe means for activating or resetting the safety valve in the event ofa possible activation malfunction. All of the operational procedures canbe done manually, automatically, or remotely by mechanical or electronicmeans. The safety valve blocking elements are tubing retrievable and canbe both surface and subsurface-controlled. The system allows forblocking means to be removed, repaired, or repositioned withoutrequiring a work over. Even with a seemingly complicated,interconnecting array of multiple blocking elements, actuating devices,resetting means, the system is, in actuality, a very simple, economical,and easy to understand device to operate. It does not necessitate acomplex mechanical system for measuring flow pressures or for actuatingand positioning the blocking means, as there are multiple knownmechanisms that can be ideally disposed for these purposes. However, itdoes include an interconnected conduit system for housing multipleblocking elements with all of the moving components isolated from theupward production flow. The invention, as described below, shows knowncompression activation and stopping devices that are all isolated fromthe harmful elements within the well. As a result, all of the mechanicalmoving parts are less likely to be gummed up, corroded, or otherwisedamaged due to sand, paraffin, and the like. Additionally, theretrievable blocking elements do not obstruct conduit flow during normaloperation, but they will halt flow if the preset pressure limit issurpassed. However, if desired, they can be positioned to restrictconduit flow beyond preset pressures without altogether stopping flow.The preferred invention can be actuated mechanically, hydraulically,electronically, manually and remotely by a multitude of know means.These means can be preset to activate the safety valve in the event ofan unsafe fluctuation in tubing pressure, flow speed or flow volume, orany other unsafe occurrence within the well bore. The safety valve isalso adaptable as a tubing string plugging means.

The blocking elements remain unengaged in a stationary position within aconduit in the safety valve during normal operation. Once the flowexceeds a predetermined limit, one or more of the preset blockingelements can be placed in the direction of flow of the safety valveconduit before coming to rest in a position to restrict flow. As statedabove, this can done automatically, but also be initiated manually fromabove by mechanical, electronic or other means whenever desired.Additionally, whenever desired, each engaged blocking element can berepositioned, removed, or reset in the unengaged chamber so that flowcan resume. All said repositioning of the blocking elements can beachieved on a wire line by implementing the use of a preferredrepositioning tool properly weighted for the type of applicationinvolved. This will insure that the positioning tool would be weightedenough to allow it to pass through the safety valve's collars in orderto properly seat.

As stated above, it is not within the scope of this invention to providenew latching and catching means for the positioning of the safety valveblocking elements as there are multiple known configurations of catchingand latching mechanisms that can ideally be disposed for this purpose.

Manual maneuvering of the blocking elements can be done from above in ashort amount of time with little expense to the operator. Optionally,the blocking elements may be removed at any time without necessitatingthe removal of the safety valve itself. Although the invention may beused to particular advantage in the production well context, it can beadapted for use in virtually all types of pipelines as well. As such,this description of the preferred use should not be construed as alimitation on this disclosure. The safety valve can utilize a variety ofknown activation devices adaptable to propel the blocking element intothe production flow conduit to halt flow. The blocking elements may beany shape capable of restricting conduit flow. In most applications, asolid cylindrical shape will effectively restrict flow in the pipeline.Simple shapes—like the solid cylinder—are more resistant to wear anddamage from flow. Additionally, the said blocking element and activationarrangement as described above in some instances can be reversed withthe said elastic communication means being housed within the blockingelement itself.

The blocking element communication activation and stopping mechanismsdescribed and shown herein are of the compression, spring and ball biastype, but the preferred invention is not limited to this type system asthey can be of a multitude of known tubing sensing, measuring andactivation devices. The preferred can additionally provide means ofselectively controlling the flow within the tubing string as well. Oncethe blocking element enters the stream of flow, a system must be inplace to stop the blocking element in a position to restrict flow. Thissystem may be, for example, a spring-loaded device capable of retractinginto the side of the conduit. The device would be preset to retract atflow rates much larger than that required to originally release theblocking element into the stream of flow. This would effectively stopthe blocking element in place and restrict flow. The activationcommunication device can further stabilize the blocking element firmlyin place from below so as to prevent it from falling into the stream offlow in case of a sudden loss of upward pressure, the When desired, theblocking element could then be pushed back into its original positionand flow could resume. In the event that the operator wanted to removethe blocking element, the blocking element could be pulled through thespring-loaded retractable device at a force great enough to depress thedevice retractors into the side of the conduit. Once through the saidretractable device, the said blocking element could be pulled out of thesafety valve, up through the production string, and out of the wellaltogether for servicing, cleaning, or replacement.

The blocking elements may be repositioned or retrieved remotely in avariety of ways. For example, a repositioning tool can be placed in aproduction well that can be used to push the blocking elements back intoa desired position. Similarly, the repositioning tool can be operatedfrom above for subse locations. The repositioning tool can be attachedto the top of an engaged or unengaged blocking element and used to placethe blocking element into another position or to pull the blockingelement completely out of the tubing string. Once the blocking means isremoved from the down hole access conduit of the safety valve, theoperator has complete unobstructed access to the tubing string. Asstated earlier, this concept may be employed in flow line applications,such as pipelines. During normal periods of flow, the blocking means ishoused unengaged within the safety valve so that it will not hinder flowor close off the well. The system can operate totally hydraulically withthe middle blocking element positioned in the unengaged chamber in thedown hole conduit of the safety valve. During the normal operation,production flow continues upward through the pipe string then into thelower safety valve conduit and on through the bypass-conduit arrangementas it travels to the surface. The above mentioned blocking element whileunengaged is held in place by a preset communication means that issensitive to the lower well conditions. Once the flow hitting the baseof the blocking element exceeds this predetermined level, the blockingelement is released from the activation communication device into thestream of flow. This added flow volume causes the said communicationactivation device to release the blocking element allowing it to travelupward with the flow and into an engaged blocking chamber after which itis immediately halted stopping member that is preset at a much highersetting that the said activation communication device. Once it stops, itis secured in place by the communication activation device that servesto stabilize the blocking element from falling back into the conduit ifthe well production flow drops.

The safety valve can also employ the opposite activation means by usinga controllable preset sensitive ball and bias spring device housedwithin the blocking element itself. When the preset setting issurpassed, this reversed blocking element is activated. When this occursthe ball and spring device retracts from the belted slot catch of theconduit wall and into the blocking element. The latter could be moresuitable in wells having frequent flow fluctuations that would cause theblocking element to make numerous movements. This type system wouldallow for the blocking element to be completely removed from time totime to have the activation settings changed or repaired.

The retrievable features, such as the said repositioning, resetting, andremoving capabilities can be omitted allowing a much simplifiedembodiment of the safety valve. While this embodiment offers completetubing string blockage involving the mechanical, electronic, manual, andhydraulic activation means as described above, this system would lacksome of the above described repositioning capabilities. Of course, withthis system complete removal and reinstallation involving a workover maybe required whenever a blocking element assumed an engaged position.While this does not have all the capabilities of the fully equippedembodiment previously described, it might prove more cost effective onlower risk wells.

The preferred invention is also a means to provide safety while downhole work is being performed such as wire line jobs. Before the downhole job begins, the middle blocking element can be removed and replacedby a wireline blocking element system including a special wirelineblocking element and an accompanying stopping cone unit that can belowered into an unengaged position following the other wire lineequipment. This system is placed above the bypass tubing arrangement.The wireline equipment passes through the safety valve while the saidblocking element and cone are placed and secured within the safety valvewith the said blocking element being placed and secured within themiddle blocking element unengaged chamber followed by the stopping conebeing placed and secured within the middle blocking element engagedchamber. The wireline which traverses through the concentric sleeves ofthe said stopping cone and wireline blocking element is then free toperform the wireline work. If the preset closure setting for thewireline blocking element is surpassed, then the excessive force of theupward flow will force the said blocking element to travel in thedirection of the said flow and into the middle blocking element engagedchamber as it is then stopped by the wire line stopping cone. Theexcessive flow will also cause the male conical slots of the wirelineblocking element to contract into the wireline itself as the saidblocking element and female stopping cone adapt thereby shutting off theupward flow movement of the conduit. If the flow diminishes to a safelevel, then the entire wire line can be removed along with all of theassociated equipment.

ADVANTAGES OF THE PREFERRED INVENTION

A few of the many advantages of the preferred safety valve system are asfollows:

-   -   Provides a total work through safety system;    -   Economical to build;    -   Economical to use;    -   Easy system for workers to understand;    -   Provides a means of resetting after engagement without pulling        the tubing string;    -   Fast acting;    -   All activation components isolated from harmful well flow        elements;    -   Easy to retrieve hydraulic blocking elements for servicing,        replacement, and removal without pulling tubing string;    -   System contains no unreliable components such as flapper valves,        ball valves, and the like;    -   Safety valve is a fail safe system with a multitude of blocking        element closing options;    -   It can be used as a choking means as it can set to selectively        restrict passage of any amount of flow;    -   It can be activated remotely by a multitude of means including        manual, electronic, hydraulic, mechanical means.    -   Saving lives, property, and environment.

DESCRIPTION OF PREFERRED EMBODIMENT

The preferred safety valve 1 may be inserted within a tubing stringwithin the well bore casing 4 of a production well. The said safetyvalve 1 as shown in the following figures is herein described utilizingan arrangement of 3 blocking elements that provide a multitude ofrestriction levels to the upward well production ranging from a totallyunengaged zero flow restriction level to a complete closure of aproduction flow conduit. The safety valve 1 as shown in FIG. 1 istotally unengaged with all of the blocking elements in an unengaged(stand by) position.

The Conduit System

Referring to FIG. 6, the entire preferred safety valve conduit system isshown. Also shown are the blocking element activation, stabilizing, andhalting units. The said combined conduit system 47 comprises 10 separateinterconnected segments including (1) the down hole access bottom endconduit segment 5 a, (2) the center conduit segment 5 b, (3) the downhole access upper conduit segment 5 c, (4) the middle conduit segment 5d, (5) the lower activation conduit segment 5 e, (6) the upper blockingelement conduit segment 5 f, (7) the lower activation offset bypassconduit 5 g, (8) the center conduit upper offset bypass conduit 5 h, (9)the center conduit lower bypass conduit 5 i, and (10) the lower offsetbypass conduit. Also shown are the three segment conduit combinations:First are the segments 5 a, 5 c, and 5 d together forming the down holeaccess conduit 46; second are the segments 5 c, 5 g, and 5 h togetherforming the center bypass arrangement 6; and third is the entire safetyvalve conduit system 47 showing the communication of all of the saidinterconnected conduits. As shown, the said conduit 46 runs from thebottom 17 of the safety valve 1 to the top 16 of the safety valve 1.This conduit 46 is in vertical communication with said production tubingstring 2 b, coupled above and below the safety valve 1.

As shown, the said offset bypass conduit arrangement 6, provides theconnection and communication combination with the said conduit segments5 a, 5 c, 5 e, and 5 f. The lower conduit segment 5 a is angularly andadjacently connected to and in communication with the lower offsetby-pass conduit segment 10 b which is in communication with andvertically connected with the lower conduit segment 5 e center conduitwhich is vertically below and in communication with the center conduitsegment 5 b which is in communication with and angularly and adjacentlyconnected to and in communication with the upper offset bypass conduitsegment 5 i. Also shown directly above the center conduit segment 5 b atthe angular confluence of the top bypass segment 5 h is the abovevertically connected service conduit segment 5 f that is vertically incommunication with the well bore service pipe access opening 2 a that isin vertical communication with the service tubing string 2 a that isextends upward to the surface platform 40.

The Hydraulic Embodiment

Referring to FIG. 1, the said offset bypass arrangement 6 is shownperpendicularly across from and parallel to the middle conduit segment 5d that houses the middle blocking element 11 in the middle blockingelement unengaged chamber 14 a. During normal operation, the formationflow is directed upwards through the production string conduit 2 b, intothe bottom of the safety valve conduit segment, 5 a. Once in the saidlower safety valve conduit segment 5 a, flow continues to travel upwardswhere it strikes the base 11 e of the middle blocking element 11. Flowis then redirected adjacently through the said offset bypass conduitarrangement 6 and on into the safety valve top conduit segment 5 c as itcontinues upwards to the top of the safety valve 16 and into theproduction string 2 b as it travels upwards towards the surface. Thesaid retrievable middle blocking element means 11 while in the saidmiddle blocking element unengaged chamber 14 a does not obstruct normalflow operation. The said blocking element 11, which is also shown inFIG. 9, is held in place within the middle blocking element unengagedchamber 14 a by a known elastic activation compression seating collartype arrangement comprising a blocking element belted slot 11 cadaptable to engage with a known pressure sensitive protrudingretractable elastic compression collar 8 a projecting from the middleconduit inner wall of the safety valve middle conduit 5 d. The saidcompression collar 8 a is shown comprising known a ball 43 and biasspring 44 together adapting with conduit collar cavity 45 forming aknown compression mechanism 42. While this said type compression collar42 is shown disposed in all of the stopping and activation collars shownand described herein, the safety valve 1 is not limited to this type ofdevice. During normal operation, the upward flow hitting the base 11 eof the said blocking element 11 places an upward force on the saidmiddle blocking element 11. As long as the flow remains below the presetfailure limit the said unengaged retractable communication activationretaining device 8 a effectively prevents the blocking element 11 fromtraveling upwards where it would halt production flow. As stated above,when the said blocking element 11 is in the unengaged position, flow ispermitted to travel upwards through the bypass conduit arrangement 6,into the down hole access conduit 5 c into the tubing string 2 b.

As shown in FIG. 2, once the preset limit is surpassed, the excessiveflow force placed on the middle blocking element base 11 e causes thesaid compressed spring and ball bias device 42 within the saidactivation collar 8 a to further compress from the said blocking elementbelted slot 15 b and into the collar cavity 45 of the said middleconduit 5 d of the said middle blocking element unengaged chamber 14 athereby releasing the said middle blocking element 11 into the increasedproduction stream of flow thus forcing the said middle blocking element11 to hydraulically travel upward into the said down hole access conduit5 c and into the said middle blocking element engaged chamber 14 b whereit is immediately retained by the middle blocking element stoppingcollar 7 a which has a much higher preset setting than the saidunengaged compression activation collar 8 a. Upward flow is then totallyrestricted as the said blocking element 11 is securely in the engagedposition within the engaged chamber 14 b. As also shown in FIG. 2, withthe said middle blocking element 11 in the engaged position, the middleblocking element belted stabilizing slot 11 d is engaged with the middleblocking element activation collar 8 a. This will prevent the saidblocking element 11 from falling down if there is a loss of upward flowpressure. At this point the well tubing string 2 b is blocked from allflow.

This prevents blowouts, fires, and explosions on the surface of theproduction well because nothing can travel any further up the productionstring 2 b.

After the well is stabilized and the operator desires to resumeproduction, the said blocking element 11 may be either removed from thewell or repositioned in the unengaged chamber 14 a. In order to removethe said blocking element 11 from the well, a known latch pulling device20 b is adapted with and lowered by wireline, slick line, or the likeinto the safety valve 1. Once lowered into the safety valve down holeaccess conduit 5 c, the said attached latch 20 b abuts the said top side11 b of the said middle blocking element 11. Then the said positioningtool latch 20 b is manipulated sideways so that it securely adapts withthe middle blocking element top side catch 11 a. Then the said latchingdevice 20 b is pulled upwards along with the attached said middleblocking element means 11 with enough additional force for it to passthrough the said middle compression stopping collar 7 a. It is thenpulled to the surface so that the blocking element means 11 can beremoved. Once the said blocking element 11 is removed, the operator hascomplete unobstructed access to the tubing string 2 b.

The said engaged middle blocking element means 11 can also be returnedto the unengaged position. This can be achieved by lowering the saidpositioning latch member 20 it into the safety valve 1 so it abuts withthe said middle blocking element top side 11 b and then further loweredwithin the said middle unengaged blocking chamber 14 a as it then placesa downward force upon the said unengaged blocking chamber compressionactivation collar 8 a that is greater than the preset activation limitallowing the said blocking element means to securely seat within thesaid unengaged chamber 14 a. Therefore the said latch 20 b must be of beof sufficient weight to allow it push the said blocking element 11through the said middle blocking element engaged activation collar 8 aon its way to the said unengaged chamber 14 a. When these components arein securely place within the safety valve 1 the entire conduit is openand normal flow can resume.

The Mechanical Embodiment

As shown in FIG. 3, the said middle blocking element 11 is housed withinthe middle blocking element unengaged chamber 14 a of the preferredsafety valve 1. During normal production flow the said middle blockingelement 11 serves to divert the upward flow which is deflected by themiddle blocking element base 11 e as it is directed into and upwardsthrough the bypass arrangement 6 as it travels to the surface. Thefigure also shows the lower compression communication collar 8 bsituated within the wall of the lower conduit 5 e in the lower blockingelement unengaged chamber 15 a. The said elastic activationcommunication device 8 b comprising of the said ball and bias springdevice 42 is shown in communication with and protruding from said thecollar cavity 45 of the said lower blocking element unengaged chamber 15a into the lower blocking element belted slot 10 c. The said activationcommunication collar 8 b is shown with the said ball and spring biasmechanism 42 within and in communication with the said lower blockingelement activation belted slot 10 c of the lower blocking element 10which is shown within the lower blocking element unengaged chamber 15 ahoused within the lower conduit 5 e. The said lower blocking element 10,which is shown in FIG. 8, is firmly held in place within the saidunengaged chamber 15 a by the preset communication activation collar 8b. The belted slot 10 c surrounding the said blocking element 10 abutsthe said elastic flow sensitive ball and bias spring device 42 which isin communication with the said activation collar 8 b located in theinner wall of the lower conduit 5 e. The lower bypass conduit 5 g incommunication with the adjacently adjoining safety valve down holeaccess bottom end conduit 5 a angularly directs tubing flow forcedirectly against the activation plunger rod base 10 i which is at theterminus of the said bypass tubing conduit 5 g. During normalproduction, the said production flow force is transferred from the saidplunger rod base 10 i to the belted slot 10 c of the lower blockingelement 10 which is in communication with and held firmly in place bythe said compression collar communication device 8 b which hold the saidlower blocking element securely within the lower blocking elementunengaged chamber 15 a. The blocking elements as shown in FIGS. 8, 9,10, and 17 all have the same belted slot configuration for activationand stabilization. While the said belted slots provide an ideal meansfor the purposes described herein, an alternative reversed blockingelement might be desired for certain applications. As shown in FIG. 18,is a reversed blocking element with a ball and spring bias activationmeans 42 within the blocking element itself.

As shown in FIG. 4, when the flow force exerted on the said plunger rodbase 10 i exceeds the preset failure limit, the said excessive forcetransferred to the said protruding ball and bias spring device 42causing the said ball 43 and bias spring 44 retract into the said collarcavity 45 of the lower communication activation collar 7 b of the lowerblocking element unengaged chamber 15 a. This retraction movementremoves the said ball 43 from the lower blocking element activation slot10 c allowing the lower blocking element activation spring 10 g that iswrapped around the lower blocking element activation plunger rod 10 h toinstantly expand. This vertical expansion combined with the additionalupward flow force causes the said plunger rod 10 h to move upwardsforcing the plunger rod follower disk 10 j to instantly transfer thesaid lower blocking element 10 from the said lower blocking elementengaged chamber 15 a upwards into the said lower blocking elementengaged chamber 15 b. Once the said blocking element 10 enters the saidengaged chamber 15 b, it is immediately halted by the said lowerblocking element engaged chamber halting collar 7 b which has a muchhigher preset failure setting than that of the said lower blockingelement activation collar 8 b. The said blocking element 10 is firmlyand securely stabilized within the said engaged chamber 15 b by the saidsupporting plunger rod disk 10 j which is firmly held in place by thecombined upward force provided by the said activation spring 10 g andupward flow emitted from said lower conduit bypass 5 i. This actionhalts all upward flow.

Mechanical Repositioning of Lower Blocking Element

A third blocking element 12, is shown in FIG. 8. This upper blockingelement 12, as shown in FIG. 1, is housed within the upper blockingelement unengaged chamber 12 h within the said conduit segment 5 f thatis vertically above and in communication with the said center conduitsegment 5 b and adjacently in communication with the said upper bypassconduit segment 5 h. During normal operation, the said upper blockingelement 12, is vertically positioned inverted within in the said upperblocking element unengaged chamber 12 h within the said conduit segment5 f directly above the confluence of the said top bypass conduit segment5 h and the said center conduit segment 5 b. Here the said top side ofupper blocking element 12 a serves to divert the normal upward flowproceeding from the center conduit 5 b into the upper bypass 5 f as itflows toward the surface. The said blocking element 12 is shown beingheld in place by a retractable compression catch 8 c. This said blockingelement 12 is further held in place within the said upper blockingelement unengaged chamber 12 h by the upper the blocking elementpositioning tool convex latch guide 19 a of the positioning tool 18. Thesaid latch guide 19 a is shown downwardly abutting the upper blockingelement concave conical base 12 g. A known traversing actuatorcontrolling mechanism 33 is shown within a housing 34 engaged with thesaid positioning tool 18 as it extends downward into the upper conduitsegment 5 f of the safety valve 1 and through the tubular opening sleeve12 b of the unengaged upper blocking element 12 terminating just beyondthe upper blocking element top side 12 a. Various embodiments of thesaid actuator 33 are commonly found on all sorts of equipment that havetraversing movements such as pumps, stitching machines, elevatingequipment, and the like. Likewise, the said actuator movements andpowering of the said movements can be generated by a multitude of knownmeans, with said power generating means being adapted to control thesaid movements. As shown, the said actuator is 33 is shown physicallyattached to the said positioning rod 18 a which extends from the saidactuator housing 33 on the well's surface side platform 40 to the topside of the said upper blocking element 12 of the safety valve 1. Thesaid actuator 33 controls all of the traversing up and down and sidewardmovements of the said positioning tool 18. The said movements of thesaid actuator can be remotely controlled by variety of known electronic27 and manual 37 devices. The actuators and powering choices can be madeon a application type basis. The said positioning tool 18 is shownattached to the said traversing actuator 33 so that it can effectivelyposition and reposition the said upper blocking element 12 from anyposition extending from the upper blocking element unengaged activationcollar 8 c to the lower blocking element unengaged collar 8 b. The saidactuator housing 34 can isolate all moving components within theactuator housing 34 from any of the harmful pressures or elements. Asshown in FIG. 3, these components can also include the positioning toolactuator spring 35, the said spring propulsion base 39, and the saidspring follower disk 36 all of which can be positioned within the saidhousing 34. The said actuator 33 being housed within the positioningtool actuator housing 34. As shown FIGS. 3 and 18 show the saidpositioning tool actuator 33 housed within the positioning tool actuatorhousing 34 positioned on the surface platform 40, the said actuator 33can be also be configured to be housed within the safety valve 1 itself.As stated above, since the said actuator 33 generates all traversing upand down and sideward movement of the said positioning tool 18, likewiseall maneuvering of the said upper blocking element 12 and latching means20 are also controllable from above by the said actuator 33 as well.Here the said positioning tool latch means 20 is shown adapted with andforming the downward end of the said positioning tool 18 as it protrudesfrom the upper blocking element top side 12 a of the said upper blockingelement 12. The said latch 20 and said positioning tool guide 19 a areshown adapted with the said positioning tool 18 in FIG. 19. The saidupper blocking element 12 is shown in FIG. 1 vertically inverted withinthe said upper blocking element unengaged chamber 12 h. As shown, thesaid conical latch guide 19 a of the said positioning tool 18 isconcentrically inserted inside the corresponding tubular opening sleeveof the upper blocking element base 12 g with the said latch 20 andattached latch lifting pegs 20 a within the upper blocking element topside latch lifting peg housing slots 12 c. Even though at times as isshown in FIG. 1, the positioning tool latch 20 and latch pegs mayprotrude slightly from the top side 12 a of the said upper blockingelement 12, no normal upward flow will be adversely affected. The saidpositioning tool 18 and said latching members are used in variousrepositioning the lower blocking element 10 being adaptable to push andpull the said lower blocking element 10. To push the said lower blockingelement 10, the said positioning tool 18 is lowered to abut and thendownwardly push the top side 10 b of the lower blocking element 10 intothe unengaged chamber 15 a or any other point between the said lowerblocking element engaged chamber 15 b the said unengaged chamber 15 a.To pull the lower blocking element 10 upward, the said positioning toolis lowered so that the positioning tool conical guide 19 a fits into thecorresponding upper blocking element conical base 12 g as describedabove. It is then perpendicularly maneuvered sideways so that thepositioning tool guide notch 19 b engages with the corresponding upperblocking element positioning guide slot 12 h which will firmly hold thetwo in place so that there can be no sideward slipping between the twoduring the said movements. Then the positioning tool 18 is lowered toabut the top side of the lower blocking element 10 b and again isperpendicularly maneuvered sideways so that the positioning tool latchlifting pegs 20 a fit directly under the lower blocking element top sidecatch 10 a so that the said pegs can engage with the said tops catch 10a to provide a lifting support to the said lower blocking element 10.The said positioning tool 18 lifts the said upper blocking element 12into another desired position within the said safety valve 1.

In order to release the said lower blocking element 10, the saidengagement procedure is reversed allowing the positioning tool to pullupper blocking element 12 upward into the said unengaged chamber 12 h.As shown in FIG. 7, the said blocking element 12 can also restrict flowas it can be vertically maneuvered by the positioning tool traversingactuator 33 up and down within the upper conduit 5 f and center conduitsegment 5 b to be selectively positioned to restrict flow as a chokingmeans or act as a fail safe tool in the event that another blockingelement means somehow failed to properly engage as it can be manuallylowered into the lower blocking element engaged chamber 15 b tocompletely halt upward production flow.

As shown in FIG. 3, the preferred safety valve is attached to and incommunication with two upper strings: the positioning and service toolrod string 2 a, and the down hole production flow tubing string 2 b. Asdescribed, flow travels up the production string 2 b. The purpose of thepositioning tool rod service string 2 a above the safety valve conduitsegment 5 f is to provide operators at the surface with access tomaneuver safety valve blocking elements 10 and 12, retractable catches,spring 27, plunger rod 29, and bypass-conduits located within orconvenient to the conduit segment 5 e, 5 b and 5 f. However, the saidservice tubing string 2 a could be converted to an additional productionstring if so desired. As FIG. 1 shows, some of the safety valvecomponents, including bypass conduit segments 9 a and 9 b, blockingelements 10 and 11, retractable catches 8, 21, and 36, plunger rod 14,spring 15, seat 2 can be much the same and are also isolated fromharmful well elements.

As shown in FIG. 5, the upper blocking element 12 is in the process ofvertically repositioning an engaged lower blocking element 10 from thelower blocking element engaged chamber 15 b to the lower blockingelement unengaged chamber 15 a. The positioning tool rod conical notchedguide 19 a is lowered into the upper blocking element concave conicalslotted base 12 g and turned so that the said notched guide 19 a engageswith the said upper blocking element slotted conical base 12 g. Afterthe said engagement, the said positioning tool 18 pushes the said lowerblocking element 10 into the said unengaged chamber 15 a so that it willengage the lower blocking element activation slot 10 c with the lowerblocking element activation communication collar 8 b. At this point, thepositioning rod can be turned so that the positioning tool latch pegsengage with the lower blocking element top side catch 10 a enabling thepositioning tool 18 to pull the lower blocking element 10 to anotherposition above the lower blocking element unengaged chamber 15 a. Tomove upward, the said positioning tool 18 is not turned to engage withthe said lower blocking element catch 10 a leaving the upper blockingelement 12 free. Then the positioning tool 18 is then raised causing thepositioning tool latch lifter pegs 20 b to upwardly engage with the topside lifter peg slots 12 c within the upper blocking element concentrictubular sleeve 12 b of the said blocking element 12 which provides theupward movement seating support of the said upper blocking element 12and then continues pulling the said upper blocking element 12 into theupper blocking element unengaged blocking chamber 12 h and seating itwith the upper blocking element activation collar 8 c thereby allowingthe positioning tool 18 pull the upper blocking element 12 upward intothe upper blocking element unengaged chamber 12 h. The safety valve 1 isthen open for upward flow.

The Wire Line Embodiment

FIG. 13 shows the wireline blocking arrangement showing an unengagedwireline blocking element 13 within the middle blocking elementunengaged chamber 14 a of the safety valve 1 positioned to providesafety for wireline work carried on down hole within the well conduit 2b. The figure shows the slotted conical top side 13 a of the saidblocking element 13 with a series of parallel, hollowed out slots 13 barranged vertically within and surrounding the said concave conical topside 13 a of the said blocking element 13. Also shown within the saidblocking element 13 is the concentric tubular sleeve 13 c that extendsfrom the said blocking element 3 from top side 13 a to bottom side 13 d.This said sleeve 13 c is adaptable to provide vertical traversingmovement of a wireline 3 within the said sleeve. Shown in FIG. 16 is thewireline adaptable concave, conical latching means 20. The said latchingmeans 20 which also serves to provide blockage of upward flow during theactual wireline work, is adaptable to position the said wirelineblocking element 13 within the down hole access conduit 46 of the safetyvalve. Shown in FIG. 13 is the wireline blocking element 13 positionedwithin the unengaged middle blocking element unengaged chamber 14 a andis adapted with the middle blocking element engaged stopping collar 7 a.As stated above, the said latching means 20, so positioned, serves toprovide the blockage of normal upward flow during the wireline job.However, prior to starting the wireline job, if desired for addedsafety, the center conduit 5 b can be blocked off to further insure nopassage of upward flow around the wireline blocking element. To achievethis blockage, the positioning tool rod 18 a lowers the upper blockingelement into the lower blocking element engaged chamber 15 b and issecurely held in place there by the lower blocking element engagedstopping collar 7 b thus preventing any upward flow through the bypassarrangement 6. Then the said wireline blocking element 13 with the topside 13 a up and wireline positioning latch 20 c are insertedrespectively on a wireline and lowered into the well tubing string 2 band into middle blocking element unengaged chamber 14 a of the safetyvalve where it is securely engaged with the middle blocking elementactivation collar 8 a. Once all of the above equipment is positioned forwireline work as stated above, the desired wireline tasks can begin.However, if during the wireline work, there is a dangerous upward flowsurge that exceeds the preset limit, then the said middle activationcommunication unit 8 a will elastically release the said blockingelement 13 hydraulically into the stream of flow, as shown in FIG. 14.Even though the wireline 3 is reciprocating up and down in the well,this increased flow is sufficient to cause the communication device 8 ato release the said blocking element 13 into said the stream of flowcausing it to travel vertically upwards into the said middle blockingelement engaged chamber 14 b immediately hitting and engaging with thesaid wireline conical latching unit 23. When this happens, the increasedupward force causes the said conical slots 13 b on the top male conicalside 13 a of the said wireline blocking element means 13 to compresstogether forming a tight gripping force on the wireline 3. If needed, ano-ring can be placed in a shown grooved slot 26 for an even tighter fit.The upper belted slot 13 j on the male conical top side 13 a of thewireline blocking element 13 is adapted to engage with the correspondingstabilizing collar 20 d of the said wireline latching unit 20 c. At thispoint the upward flow within the safety valve down hole access conduit46 and the well tubing string is restricted along with the traversingwireline movement thus preventing a blowout. Once it is deemed safe tocontinue down hole work, the surface control then can dispose thewireline 3 to pull the blocking equipment from the safety valve 1 byplacing an upward pulling force greater than that of the said middleblocking element stopping collar to remove the wireline equipment andthe said safety valve blocking equipment from the well. In order toresume down hole wireline work, the said safety valve wireline blockingequipment can be repositioned as described above. After the wireline jobis completed, then the removed blocking element 11 can be reinsertedinto the safety valve 1 and reset in the unengaged chamber 14 a. If thesaid upper blocking element 12 is in the engaged position, then the saidupper conduit positioning tool 18 and attached upper blocking element 12can be raised and then securely reposition the upper blocking element 12within said upper blocking element unengaged chamber 12 h. After theseoperations are completed, then upward flow can resume.

The said wireline blocking system can also be adapted to provide safetyfor other types of applications such as pumping units, pipelines and thelike.

An Alternate Hydraulic Embodiment

Another embodiment 9 that could be cost effective for the low risk wellsis the hydraulic only arrangement as shown in FIG. 11. Shown is thepreferred safety valve 1 with the bypass arrangement 6 opposite themiddle blocking element unengaged housing chamber 14 a. This embodimentis shown excluding the said upper and lower blocking embodiments asshown and described above. However, the blocking and repositioningoperations for the middle blocking element 11 and the wireline blockingelement 13 of this embodiment function the much the same way as thosepreviously described above and as shown in the previous figures. Withthis system, blocking and positioning procedures of the said middleblocking element 11 and said wireline blocking element 13 can beachieved as described above. Even though some of the positioning andblocking means in other embodiments as described above are not included,this limited system 9 may be desired in low risk wells such as stripperwells and other low production wells. As shown in FIG. 12, the preferredinvention can embody the above described wireline blocking system withina housing mandrel that has no bypass conduits. This unit will functionexactly the same as the wireline blocking system previously described.However, this is a wireline only device that would be ideal for wirelinecompanies to have for their own use’.

CONCLUSION

In conclusion, it is shown that the present invention and theembodiments disclosed herein and those covered by the associated claimsare well adapted to carry out the objectives and ends set forth. Certainchanges can be made in the subject matter without departing from thespirit and scope of this invention. It is realized that changes arepossible within the scope of this invention and it is to be understoodas referring to all of the equivalent elements or steps, the followingclaims are intended to cover the invention as broadly as legallypossible in whatever form it may be utilized.

A BRIEF DESCRIPTION OF THE DRAWINGS

The drawings below show only a few of the many possible configurationsof the preferred system and should not be construed to limit the scopeof the invention.

FIG. 1. Partial sectional view of the preferred safety valve unengaged.

FIG. 2. Partial sectional view of the preferred safety valve with thehydraulic blocking element the engaged position.

FIG. 3. Partial sectional view showing the safety valve repositioningmeans repositioning the lower blocking element.

FIG. 4. Partial sectional drawing of the preferred safety valvemechanical blocking element in the engaged position.

FIG. 5. Partial sectional view of positioning tool repositioning lowerblocking element means.

FIG. 6. Partial sectional view showing the positions of the preferredconduits, bypasses, stopping units, and activation devices.

FIG. 7. Partial sectional side view of safety valve showing the upperblocking element means in an engaged position

FIG. 8. Side view of the upper blocking element.

FIG. 8 a. end view of the upper blocking element

FIG. 9. Side view of the middle blocking element.

FIG. 10. Side view of the lower blocking element.

FIG. 11. Partial sectional side view of the preferred safety valve witha limited bypass arrangement.

FIG. 12. Partial sectional end view of safety valve limited bypassarrangement.

FIG. 13. Partial sectional detailed side view of unengaged wire lineblocking unit

FIG. 14. Partial sectional detailed side view of engaged wire linesafety arrangement

FIG. 15. Isometric side view of upper blocking element.

FIG. 16. Partial sectional side view of the wireline latching unit

FIG. 17. Partial sectional side view of the wireline blocking element

FIG. 18. Partial sectional side view of safety valve

FIG. 19. partial sectional side view of upper positioning tool withlatch and Guide.

What is claimed is:
 1. A safety valve having a housing with a top sideand a bottom side for controlling flow, comprising: blocking elementmeans; means for directing flow around said blocking element means; and,means for controlling said blocking element means such that flow isunrestricted or restricted through the safety valve.
 2. The safety valveof claim 1, further comprising: a first conduit within the safety valvehousing, wherein said first conduit runs from top side of said housingto bottom side of said housing; and, wherein the said first conduit isin communication with a lower production string attached to the saidbottom side of the said safety valve housing and the upper productionstring attached to the top side of the said safety valve housing; and,wherein a first blocking element means positioned unengaged within saidfirst conduit such that upward flow striking the said blocking elementredirects said flow into an upper bypass conduit that is incommunication with said first conduit so that upward flow is directedaround said first blocking element and through said first conduit ofsaid safety valve and into said upper tubing string; and when said firstblocking element is in an engaged position within said first conduitsaid upward flow is restricted in said safety valve.
 3. The safety valveas in claim 2, wherein said means for controlling said first blockingelement means such that said flow is unrestricted or restricted throughthe safety valve further comprises a first elastic compressioncommunication catch means housed within said conduit, and wherein saidfirst catch is adapted to hold said blocking element in the saidunengaged position within said conduit; and, a second elasticcompression catch means is housed with the said conduit, and wherein thesaid second catch is adapted to halt said blocking element in theengaged position, whereas the said first catch being adaptable toprovide upward support to secure said blocking element in the saidengaged position.
 4. A safety valve as in claim 3 wherein: said safetyvalve is a sub surface safety valve;
 5. A safety valve as in claim 3,wherein: said first blocking element is retrievable.
 6. A safety valveas in claim 3, wherein said safety valve further comprises a secondconduit originating in the said safety valve housing; and, wherein saidsecond conduit is in communication with a second upper tubing stringattached to the top side of the safety valve housing; and, wherein afirst lower bypass conduit is in communication with the said firstconduit and the second conduit; and wherein a second blocking element ishoused within the said lower second conduit; and, wherein said secondblocking element has an unengaged position such that said upper flowpasses through said conduit; and, an engaged position such that saidflow is restricted; and, a third catch housed within the second conduitwherein the said third catch is adapted to hold said second blockingelement within the said unengaged position thereby allowing said upwardflow to pass through the said lower second conduit; and, a fourth catchhoused within the second conduit wherein the said fourth catch isadapted to halt the said second blocking element in the engaged positionthereby restricting flow within the second conduit.
 7. A safety valve asin claim 6, further comprising: a plunger rod having a lower rod portionand an upper disk portion, wherein said plunger rod is housed within thesaid lower second conduit and said lower plunger rod portion fits intothe said lower bypass conduit; and a spring is positioned between saidupper disk portion of said plunger rod and said lower second conduit;and, the said second catch is adaptable to hold said plunger rod in asaid unengaged position within the said lower second conduit.
 8. Asafety valve as in claim 7, wherein: said safety valve is a sub surfacesafety valve
 9. A safety valve blocking element as claimed in claim 7,wherein: said second safety valve blocking element is retrievable'
 10. Asafety valve as in claim 7, further comprising: a third blocking elementin an unengaged position within the said second conduit so that upwardflow from said upper bypass conduit hitting the said third blockingelement is redirected into the said first conduit; and, when loweredfrom above into and securely held in an engaged position restrictsupward flow.
 11. A safety valve as in claim 1, further comprising: afourth blocking element; wherein said blocking element has a top sideand a bottom side; and whereas said blocking element contains a verticalconcentric tubular sleeve extending from said bottom side of saidblocking element to said top side of said of said blocking element; andwherein said top side of said blocking element is conical containing amultitude of compression slots positioned from the top side conicalopening to the bottom side of the said conical top; and, said blockingelement contains a compression slot adaptable with a said conduitcompression catch.
 12. A safety valve as in claim 11, further comprisinga blocking element catch member wherein said catch member has a top sideand a bottom side; and whereas said catch contains a concentric tubularopening sleeve; and, said sleeve extends from the said top side to acentrically positioned concave conical catch adaptable to tightlycontain said corresponding fourth blocking element; and, said catchmeans further contains a catch to engage with the said second catch withthe said first conduit; and said catch has a slotted catch to engage andsecure the said fourth blocking element when the said fourth blockingelement is in the engaged position.
 13. A preferred method utilizingembodiment 1 for controlling the flow within a subsurface well tubingstring, and whereas said safety valve a disposes a hydraulic proceduraloperational sequence by; positioning safety valve in tubing string ofwell; and said first blocking element is positioned firmly in place by afirst locking collar so that upward flow from tubing string afterentering safety valve conduit strikes base of said blocking element; andsaid flow is then redirected into a conduit arrangement bypassing saidblocking element in the safety valve; and, flow then is directed pastsaid first blocking element and into top conduit of safety valve thenflowing to the surface; and when flow exceeds the designated resistancelimit of the first blocking element locking collar, said first blockingelement is vertically released into the upward conduit flow whereas saidupward flow then propels said first blocking element into the secondlocking collar position effectively halting said blocking element meanswhile the said first locking collar below stabilizes the said blockingelement means in place thereby cutting off all upward flow within safetyvalve; and whereas said first blocking element can be repositioned inoriginal unblocked position once the well is deemed safe to reenter by acontrolled downward force placed on top side of said first blockingelement.
 14. A fail safe method of controlling the flow within a welltubing string with a subsurface safety valve involving the mechanicalprocedural operational sequence by: removing the needed joints of welltubing string so that the desired safety valve depth will be attained;then, preset safety valve communication activation and halting devices;securely place the positioning tool within the upper blocking elementmeans; place the safety valve in the tubing string; adjoin saidpositioning tool with above controlling means; safety valve is thenprepared and ready for use at which time the tubing string is unblockedto all upward flow.
 15. A method for providing safety for wireline jobsinvolving these steps: lower the safety valve positioning tool latchinto safety valve; and then engage latch with middle blocking element toside catch and remove the safety valve middle blocking element meansfrom the tubing string; then place the wireline safety valve latchingmeans above the wireline blocking element means top side up on thewireline above the various installed wireline equipment; and then placethe said wireline in the well with the said wireline equipment; and,endeavor to place the wireling blocking element means latch at theposition so as to engage it securely with the middle blocking elementengaged stopping unit; and then place the wireline blocking elementmeans to securely seat in the middle blocking element means unengagedchamber; and begin the wireline work; then after job is complete removethe wireline equipment and wireline blocking element means and wirelineblocking element means stopping latch; and then reinstall the middleblocking element means top side up within the middle blocking elementmeans unengaged chamber; and resume normal production.